Work

CGM ‐derived average glucose is more strongly associated with microvascular complications than HbA1c in type 1 diabetes

Year: 2025

Type: article

Abstract: AIMS: To compare the associations of HbA1c and continuous glucose monitoring (CGM)-derived average glucose with microvascular complications in adults with type 1 diabetes, and to assess the clinical utility and stability of metrics capturing glycation discordance. MATERIALS AND METHODS: Observational assessment of 9023 paired measurements of CGM data (14 days) and HbA1c in 2721 adults with type 1 diabetes. CGM metrics, HbA1c, and markers of discordance between HbA1c and CGM average glucose were associated with prevalent retinopathy (any and proliferative) and microalbuminuria. RESULTS: HbA1c was higher than expected in older individuals (62 mmol/mol [54-71] age >45 vs. 61 mmol/mol [52-71], p = 0.004) and in women (62 mmol/mol [54-71] vs. 61 mmol/mol [53-71], p < 0.001) despite lower or similar average glucose levels. Fewer than one-third of individuals remain within the same HbA1c-average glucose discordance category over time. HbA1c (p < 0.001), average glucose (p < 0.001), CV glucose (p < 0.001), and socioeconomic deprivation (p = 0.003) were all independently associated with retinopathy risk (with similar results for proliferative retinopathy). Higher glycation was associated with a lower likelihood of prevalent retinopathy (p < 0.001). CONCLUSIONS: CGM-derived average glucose appears superior to HbA1c as a marker of prevalent microvascular complications. These data challenge the high-glycator hypothesis and also suggest glucose variability may be an independent risk marker for microvascular disease.

Source: Diabetes Obesity and Metabolism

DOI: 10.1111/dom.70365